Reducing end-to-end transmission delay in P2P streaming systems using multiple trees with moderate outdegree

We propose an overlay consisting of multiple trees with moderate outdegree to reduce end-to-end transmission delays in P2P media streaming systems. In real-time media streaming, lower end-to-end delays lead to less waiting time before playback and hence improve interactivity. A theoretical analysis of degree-bounded trees reveals that an optimal number of multiple trees can be chosen by considering the trade-off between the total propagation delay and the queueing delay experienced at intermediate peers. A distributed protocol is presented that allows peers to build multiple degree-bounded trees. From extensive packet-level simulations, we observe that the worst end-to-end transmission delay is minimized when the peerpsilas outdegree, or fan-out, is between 4 and 6 for realistic simulation parameters. This matches well with the predictions from our analysis.